Friday, March 8, 2013

Researchers Warn Of Aggressive Mosquito In Florida

GAINESVILLE, Fla. — If mosquitoes were motorcycles, the species known
as Psorophora ciliata would be a Harley-Davidson — big, bold,
American-made and likely to be abundant in Florida this summer.

Just how abundant is a matter of speculation, but University of Florida
entomologist Phil Kaufman says last year the state had a bumper crop of
the huge, biting insects, which are sometimes called gallinippers. He
said there may be a repeat on the way.

“I wouldn’t be surprised, given the numbers we saw last year,” said Kaufman, an associate professor with UF’s Institute of Food and Agricultural Sciences. “When we hit the rainy cycle we may see that again.”

The gallinipper is a floodwater mosquito, with females laying eggs in
soil at the edges of ponds, streams and other water bodies that
overflow when heavy rains come. The eggs can remain dry and dormant for
years, until high waters cause them to hatch, Kaufman said.

Last June, Tropical Storm Debbie caused flooding in many parts of
Florida and unleashed large numbers of gallinippers, along with other
floodwater mosquitoes.

To help residents understand the species better, Kaufman and UF/IFAS
entomology graduate student Ephraim Ragasa created a document on
gallinippers for the department’s “Featured Creatures” website. It’s now
available on IFAS’ Electronic Data Information Source, at http://edis.ifas.ufl.edu/in967.

Native to the entire eastern half of North America, the insect has a
body about half an inch long, with a black-and-white color pattern that
makes it resemble a super-sized version of the invasive Asian tiger
mosquito.

As with other biting mosquitoes, only the female gallinippers are
blood feeders; males survive on flower nectar. The species is
notoriously aggressive and has a painful bite.

“The bite really hurts, I can attest to that,” Kaufman said.

Even in the larval stage, gallinippers are fearsome. Most mosquito
larvae are content to subsist on decaying plant matter floating in the
waters where they develop, but gallinippers are omnivorous, devouring
other mosquito larvae and even tadpoles.

With that trait in mind, observers have suggested the gallinipper
might be a good candidate for biological control efforts, using the
larvae to reduce populations of other pest mosquitoes. But that strategy
has a fatal flaw, Ragasa says – it results in more gallinippers.

“That kind of defeats the purpose of using them for biocontrol,” he said.

Gallinippers can be warded off with repellents containing DEET,
though Kaufman said that due to their large size they may be more
tolerant of the compound than smaller biting mosquitoes. Other
precautions include wearing long pants and long-sleeved shirts when
venturing into wooded areas, especially places where standing water
collects after rain storms.

There are a few good things one can say about this mosquito: It isn’t
considered a significant vector of mosquito-borne illness affecting
people or animals. And human activity doesn’t seem to boost its
populations.

“This isn’t one where you build a subdivision and start to see more,” Kaufman said.